Integrated flex winding realisation for 3D PCB converts

Abstract

The implementation of flexible printed circuit technology in power magnetic winding design is investigated. At first this implementation is considered as a stand-alone winding technology for discrete magnetic components and thereafter it is applied as an integral winding technology, enabling enhanced manufacturing possibility for an integrated 3D converter concept, discussed herein. Optimisation of both the material- and layer usage in the winding stack realisation is found to be the key to minimising the manufacturing cost of such a PCB fabricated winding stack, as well as improving its interconnection reliability. The associated folding pattern of the winding panels, in conjunction with the winding patterns themselves, receive meticulous attention during the proposed winding design method. The manufacturing complexity and cost advantages of using double sided, flexible printed circuit technology to realise a planar winding stack by the proposed folding method, that would otherwise require a substantial number of costly, rigid printed circuit layers, is brought to the forefront. Also the possibility to exploit the parasitic elements of the magnetic component as functional resonant tank elements, using the folding pattern design is investigated. Practical validation of an integrated magnetic component suitable for a 3D PCB converter is presented along with critical evaluation of the results.